Yes it is possible. Both Exterior and Interior NPT threads. I am not sure what size you want to do, nor do I know what type of threadmill that you have access to, but this is an example of a 2"-11 1/2 I.D NPT thread using a 5/8 diameter shank threadmill, with .82 cutting dia. The insert is a 21mm height -11 1/2 pitch , 4.7mm thick, and 12mm from back of insert to end of teeth . (The insert is specific to the pitch of thread.) So if you have a single point, this would not work for you. But single point thread milling can be done as well with some modification.
(NO TOOL RADIUS COMPENSATION D1=0)
***I HAVE A PROGRAM YOU CAN USE TO THREADMILL ANY ID/OD THREAD GIVEN FROM A MANUFACTURER & DEALER OF THREADING INSERTS & TOOLS. I USE THEM ALL THE TIME. IT HAS A POST PROCESSER BUILT IN TO POST YOUR PROGRAM, SO JUST FOLLOW THE WIZARD AND CUT YOUR THREAD! I SENT IT TO YOUR PM.